In many combustion processes, components of exhaust emissions are monitored to ensure optimum equipment performance or regulatory compliance. Monitoring of the exhaust emissions is generally performed via one or more exhaust sample ports located on the periphery of an exhaust stack to extract a sample from the exhaust stack which can then be analyzed using chemical, optical or some other means to determine the constituents of the exhaust emissions.
FIG. 1 shows an industrial engine 50 connected to an exhaust stack 52 with a prior art sample port 54 installed thereon. The engine 50 reacts fuel and oxidizer in a combustion process and expels the combustion gases into the exhaust stack 52, which in turn directs the combustion gases to the atmosphere. To facilitate emissions measurement, a sample port 54 must often be retrofitted to the existing exhaust system at the combustion equipment's point of use (i.e. in the field).
FIG. 2 shows a detailed cross-sectional view of the prior art sample port 54 installed on the engine exhaust stack 52. The installation of the sample port 54 typically involves welding a pipe, tube or weld-o-let to the periphery of the exhaust stack 52 at joint 56, for example. A cap 58 may be placed at one end of the sample port 54 to prevent exhaust gases from venting to the atmosphere when the sample port is not in use.
Due to the presence of an open flame and the possibility of sparks occurring during the welding process, many industrial locations prohibit welding in hazardous locations unless strict safety regulations and procedures are adhered to. The need for a welder combined with the additional safety requirements when welding in hazardous locations results in additional costs and production losses to the end user. Further, due to high temperatures of the exhaust surface and combustion gas, as well as significant mechanical vibration, adhesive attachment of sample ports to the exhaust stack is typically unacceptable.
Accordingly, an additional, alternative, or improved sample port remains highly desirable.
It will be noted that throughout the appended drawings, like features are identified by like reference numerals.